We report on the effect of the overall shape of a city on the flow within the street network. We start with a solid round block, aspect ratio, diameter/ height = 6. The block is subdivided into smaller blocks and step by step an increasing number of streets are introduced. In the wind tunnel visualization with helium filled soap bubbled was carried out for obtaining qualitative information about the flow pattern. The pressure distribution on the ground within the street network was recorded in 400 points. CFD predictions provided the overall flow balance; flow entering through the street portals, leaving through the exit street portals and the updraft.

The paper reports on findings from a series of experiments where the supply flow rate was varied periodically in time. All experiments were conducted in a small scale model with water as operating fluid. The flow was visualised by adding particles to the water and the streaks were recorded with a digital camera. The main result is that there exist variations that generate a role up of the base flow by generation of vortices that are shed into the stagnant region.

This paper deals with the effect of discharging the air from a diffuser elevated above the floor. The temperatures have been measured and the airflow patterns visualised close to a diffuser for displacement ventilation, results from the whole-field method (using infrared thermography) were images of different colours representing different temperatures of the air close to the diffuser.. The aim of the measurements was to see how the elevations of the diffuser above floor level and the thermal jet length of the supply could affect the near zone.